The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingAbs warning light does not come on
Wiring diagram
Refer to the abs warning light circuit (see page bc-135).
Inspection procedure
Check can communication system
Check if the can communication system dtc is output
(see page ca-34).
Result
Perform active test by intelligent tester (abs warning light)
Sele ...
Eps warning light circuit
Description
If the power steering ecu detects a malfunction, the p/s warning light comes
on. At this time, the power
steering ecu stores a dtc in its memory.
Wiring diagram
Inspection procedure
Check for dtc
Using the intelligent tester (with can vim), check for
dtcs and confir ...
Dtc check / clear
Check dtc
Connect the intelligent tester to the dlc3.
Turn the ignition switch on and turn the tester on.
Select the following menu item: body / sliding roof /
dtc.
Check the dtc(s).
Clear dtc
Connect the intelligent tester to the dlc3.
Turn the ignition switch on ...